to avoid packing i've used b-squares, and now have them on all my rigs...

if your careful to make sure the windage is the same on each and have a wind free range to check and eliminate any cross over, they only take 20 mins or so to get close to zero just using the mounts. When I mean close I mean less than 10 clicks on a 1/4 moa scope.

getting the windage sorted seems to be the trick with them, so taking time to make sure they are central before mounting them is a good start...the walther and hw rails they sit on are pretty damn straight so i've found they've needed little or no adjustment in the windage dept.

they sit on a gimble, so although it does leave the head worrying that it might come loose, once you've realised that even with a little tightness they cant shift, locking them up and leaving them, with a bit of shooting brings back the confidence. I've had them on for almost a year on one rig without any problems.

The 2 piece ones are easier to setup than the one piece ones...because you can simply undo the rear dovetail section and spin it to adjust elevation (with the other screws loose to allow both gimbles to move).

The only downside i've found with them is that they are built to very tight tolerances...the clamps arent 180 degree split, which means they need carefull effort not to scratch the scope when placed on...and the threads need to line up precisely because the threads wont allow any give on the angle before tightening...they need to be bang on or there is a danger of cross threading...a little bit of countersinking on the threads would go a long way to help.

This tolerance problem revealed itself on the one piece mount which needed to have the rail clamp exactly parallel to the block in order to be tightened...and on a dipped scope which after dipping meant the tube was a little over 30mm, which meant that the scope clamp bolts needed careful alignment. It also happend on a big nikko...which wasnt dipped, but 5 mins with a swiss file on the clamp holes saw that solved.

So, to sum up...can be a bit of work, but they completely solve the need and problems of shimming...and in my book are rock solid in performance.

I'd like to see a set of the sportsmatch mounts to see how they work as well though.